Its FlexT9 mobile application, launched in the United States last month, adds the possibility of tracing continuously from one letter to the next on a touchscreen keyboard without lifting one's finger between letters.

It also allows users to trace handwritten characters on a touchscreen instead of typing them, or to tap out the characters in the traditional way, offering to predict or correct the intended word -- much like the T9 predictive SMS text service.

After years of using numeric keypads to type text messages, users who have upgraded to smartphones are already offered full keyboards, for instance on Research in Motion's BlackBerry, and touchscreens led by Apple's iPhone.

Nuance and others are now expanding users' choices further about how they interact with their devices. Google says one-quarter of Web searches on phones based on its Android software are already done using voice input instead of typing.

"What we're looking at is the real usability of the keyboard," said John West, Nuance mobile solutions architect.

FlexT9 will now be available in UK English, German, French, Italian and Spanish in addition to U.S. English for users of Android smartphones, priced at $4.99 per download in the Android Marketplace app store.

There are no current plans for an iPhone app, as Apple does not allow its keyboard to be taken over.

Android, which is available for free to handset and tablet PC makers, overtook Nokia's Symbian as the most popular operating system for smartphones at the end of 2010.